The answer lies in increasing the intermediate resistor's value, which means we must give up on the direct coupling to the top triode's grid.

    The circuit schematic above shows a common variation of the SRPP. The intermediate resistor's value can be made much larger than in the DC version of the SRPP. In this case, 21 times larger. Now, as long as the load impedance is very high, say 1-meg, the bottom triode will see a much larger load impedance at its plate. And the top triode will function much more like a cathode follower, as its output is much less well coupled to its input. So, have we arrived? Is this the best possible circuit? No, we still have the problem that we faced from the onset: this circuit works best when it is not required to work. In other words,  the load steals the promised benefits of high gain and low output impedance. For example, loading this circuit with a 32-ohm headphone will short-circuit any notions of constant current source loading of the bottom triode.
    Making the bottom tube immune to the load can be accomplished by breaking the single current path into the top triode and load. This requires adding an additional resistor and capacitor to the circuit, as shown in the following schematic.

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For more information, read the article "Tube-Based Crossovers" in the Tube CAD Journal.
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